This is the advanced telescope that provides the same optical performance demanded by the world's leading astronomical research institutions. Similar to the Ritchey-Chrétien design used by the U.S. Naval Observatory's telescope in Flagstaff, Arizona and NASA's Hubble Space Telescope, this model uses a coma-free optical system that eliminates aberrations to provide a flat, crisp field of view. Its carbon fiber optical tube's 20" diameter aperture provides a light gathering power 5000 times greater than the human eye, ideal for observing the effects of stellar winds within the Orion Nebula, marveling at the counter-rotating cloud bands of Jupiter, or gazing at the one-trillion stars of the Andromeda Galaxy. A built-in GPS automatically orients to and tracks any of the 144,000 celestial objects stored in its on-board computer. Using a large-format CCD camera (not included), it can take pictures and videos of objects in real-time as they move in the heavens, remotely controlled from a computer using the included software or the Internet. Its 12-volt power supply powers a cooling fan and heater that prevents dew from forming on the optics. 104" H x 76" W x 42" L. (640 lbs.)